Findings demonstrate a unique and complex pattern of lifetime sexual assault history spanning childhood, adolescence, and adulthood among incarcerated women. Rates of victimization from sexual assault in childhood and adulthood were higher among incarcerated women than for national samples of women. Differences in perpetrators and patterns of abuse reported by incarcerated women compared to nonincarcerated women in the United States were revealed. Specifically, sexual assault in incarcerated women was most likely to occur in childhood, whereas previous research documented higher rates of sexual assault of females in adolescence and adulthood. Prevalence of sexual assault by partners in adolescence was actually lower for incarcerated women as compared with that reported by a representative sample of high school girls. Incarcerated women reported that sexual assault in adulthood was slightly more likely to be perpetrated by a stranger than by a partner, whereas nonincarcerated women were more likely to report sexual assault by a partner rather than by a stranger. Incarceration presents a unique opportunity for counseling and mental health intervention on a population with disproportionate risk for gender-based violence and related health consequences. Despite high rates of mental health problems for incarcerated women, the majority of mental health needs are not currently addressed within the correctional system. The development of infrastructure and a knowledge base for incarceration-based mental health care should be prioritized. Furthermore, the heightened medical needs of incarcerated women and women victimized by sexual assault throughout their lifetime as independent populations, compounded by the increased health needs of those incarcerated women victimized by violence emphasize the need for expanded medical care within the correctional system. Data were collected from 484 and women entering the Rhode Island Department of Corrections from June 2002 to February 2003. Tables, references